Price Change Percentage 24h
PRICE_CHANGE_PERCENTAGE_24H refers to the percentage change in price over the past 24 hours. Suppose, the price of a coin was $100 yesterday and it is $110 today. Since the percentage increase is 10%, PRICE_CHANGE_PERCENTAGE_24H is +10%.
This is a good indicator is how volatile a certain cryptocurrency is from day to day. Related terms include PRICE_CHANGE_PERCENTAGE.